Person:
Sanz Ortega, Julián

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First Name
Julián
Last Name
Sanz Ortega
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Medicina
Department
Area
Anatomía Patológica
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UCM identifierScopus Author IDDialnet ID

Search Results

Now showing 1 - 2 of 2
  • Item
    c-Met Signaling Is Essential for Mouse Adult Liver Progenitor Cells Expansion After Transforming Growth Factor-β-Induced Epithelial–Mesenchymal Transition and Regulates Cell Phenotypic Switch
    (Stem Cells, 2019) Almale Del Barrio, Laura; García-Álvaro, María; Martínez-Palacián, Adoración; García-Bravo, María; Lazcanoiturburu, Nerea; Addante, Annalisa; Roncero Romero, Cesáreo; Sanz Ortega, Julián; López, María de la O; Bragado Domingo, Paloma; Mikulits, Wolfgang; Factor, Valentina M.; Thorgeirsson, Snorri S.; Ignacio, Casal, J.; Segovia, José-Carlos; Rial, Eduardo; Fabregat Romero, María Isabel; Herrera González, Blanca María; Sánchez Muñoz, Aranzazu
    Adult hepatic progenitor cells (HPCs)/oval cells are bipotential progenitors that participate in liver repair responses upon chronic injury. Recent findings highlight HPCs plasticity and importance of the HPCs niche signals to determine their fate during the regenerative process, favoring either fibrogenesis or damage resolution. Transforming growth factor-β (TGF-β) and hepatocyte growth factor (HGF) are among the key signals involved in liver regeneration and as component of HPCs niche regulates HPCs biology. Here, we characterize the TGF-β-triggered epithelial–mesenchymal transition (EMT) response in oval cells, its effects on cell fate in vivo, and the regulatory effect of the HGF/c-Met signaling. Our data show that chronic treatment with TGF-β triggers a partial EMT in oval cells based on coexpression of epithelial and mesenchymal markers. The phenotypic and functional profiling indicates that TGF-β-induced EMT is not associated with stemness but rather represents a step forward along hepatic lineage. This phenotypic transition confers advantageous traits to HPCs including survival, migratory/invasive and metabolic benefit, overall enhancing the regenerative potential of oval cells upon transplantation into a carbon tetrachloride-damaged liver. We further uncover a key contribution of the HGF/c-Met pathway to modulate the TGF-β-mediated EMT response. It allows oval cells expansion after EMT by controlling oxidative stress and apoptosis, likely via Twist regulation, and it counterbalances EMT by maintaining epithelial properties. Our work provides evidence that a coordinated and balanced action of TGF-β and HGF are critical for achievement of the optimal regenerative potential of HPCs, opening new therapeutic perspectives.
  • Item
    Bone morphogenetic protein 9 as a key regulator of liver progenitor cells in DDC‐induced cholestatic liver injury
    (Liver International, 2018) Addante, Annalisa; Roncero Romero, Cesáreo; Almale Del Barrio, Laura; Lazcanoiturburu, Nerea; García‐Álvaro, María; Fernández García De Castro, Margarita; Sanz Ortega, Julián; Hammad, Seddik; Nwosu, Zeribe C.; Lee, Se‐Jin; Fabregat Romero, María Isabel; Dooley, Steven; Dijke, Peter ten; Herrera González, Blanca María; Sánchez Muñoz, Aranzazu
    Background & Aims: Bone morphogenetic protein 9 (BMP9) interferes with liver regeneration upon acute injury, while promoting fibrosis upon carbon tetrachlorideinduced chronic injury. We have now addressed the role of BMP9 in 3,5 diethoxicarbonyl-1,4 dihydrocollidine (DDC)-induced cholestatic liver injury, a model of liver regeneration mediated by hepatic progenitor cell (known as oval cell), exemplified as ductular reaction and oval cell expansion. Methods: WT and BMP9KO mice were submitted to DDC diet. Livers were examined for liver injury, fibrosis, inflammation and oval cell expansion by serum biochemistry, histology, RT-qPCR and western blot. BMP9 signalling and effects in oval cells were studied in vitro using western blot and transcriptional assays, plus functional assays of DNA synthesis, cell viability and apoptosis. Crosslinking assays and short hairpin RNA approaches were used to identify the receptors mediating BMP9 effects. Results: Deletion of BMP9 reduces liver damage and fibrosis, but enhances inflammation upon DDC feeding. Molecularly, absence of BMP9 results in overactivation of PI3K/AKT, ERK-MAPKs and c-Met signalling pathways, which together with an enhanced ductular reaction and oval cell expansion evidence an improved regenerative response and decreased damage in response to DDC feeding. Importantly, BMP9 directly targets oval cells, it activates SMAD1,5,8, decreases cell growth and promotes apoptosis, effects that are mediated by Activin Receptor-Like Kinase 2 (ALK2) type I receptor. Conclusions: We identify BMP9 as a negative regulator of oval cell expansion in cholestatic injury, its deletion enhancing liver regeneration. Likewise, our work further supports BMP9 as an attractive therapeutic target for chronic liver diseases.